Scraping tool



x. 0. JOHNS 0N. SCRAPING. TOOL.

APPLICATION FILED DEC. 20, I920.

Patented 1m 3,1922,v

xen, .ronuson, or TOLEDO, c1510;

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Yr Application filed December 20,1920. Serial No. 431,830.

To alZ'wiwm z'zfimay concern:

Be it lmown that 1, Xe JOHNSON, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ghio, have made an Invention Appertaining to Scraping Tools; and I do hereby declare the followingto be a fulhblear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, referencebeing had to the accompanying draw-. ings, and to the characters. of reference marked thereon, which form a part of this specification. 1

a his invention relates to a tool for scraping cylindrical surfaces, and particularly for use in scraping the inner walls of engine cylinders.

The interior side walls of engine cylinders frequently become scored, from one-cause or another and the scorings are then filled with metal. After filling the scorings itisnecessary to dress down or scrape away the surface metal to provide the wall with a per-' fectly smooth cylindrical surface. The primary ob ect of my nvention is-the provision of a simple and eflic1ent-.tool for use particularly in scraping or dressing down the filled surface of engine surfaces to correct cylindrical form, and which is easlly and quickly ad ustable to operate on cyl1n-' ders of different diameters. Further objects forms, a preferred embodiment-thereof is illustrated in the accompanying drawings, in which- 1 Fig. 1 is a side view of a tool embodying the invention with parts broken away. Fig. 2 is an end view thereof in scraping engagement with a cylinder, and Fig. 3 is a face view of a scraper knife used in connection with the tool.

Referring to the drawings, 1 and 2 designate the two cooperating members of a clamping head for releasably carrying a scraper knife or blade 3 therebetween with its scraping edge projecting therefrom. The member 2 is carried by a sleeve or hollow stem a projecting from the outer face thereof, preferably at right angles thereto, and the member 1 is in threaded engagement Specification of Letters Eatent.

detailed descrip-.

Patented Jan. 3, 1922.

with the outer end of a stem or rod 5, :which projectsfrom a handle 6 forwardly through the sleeve 4 and member 2 into the member 1 Thestem 5 has a shoulder 7 in engagement with the outer end of the sleeve 4 to limit the movement of the stem therein during a threading. of the stem tothe member 1, whereby a threading of the stem in one direction into themember 1 .Will cause it to have clamping engagement withthe blade 3 in opposition to the member 2. One of the clamping members, 1 in the present instance, has a lug 8 projecting therefrom at its upper edge toward the other member for coaction therewith to prevent a tilting of the member 1 by reason of its clamping engagement with the blade 3 at the opposite side'of the head axis. One of the members, 2 in the present; instance,.also has a {pair of studs 9' projecting therefrom through. registering apertures in the member l to prevent a relative turning of the clamping members. The edges of the clamping members from which the'blade 3 projects are preferably, but" not necessarily given a slight convex curvelongitudinally thereof, and one member, the member 2 1n the presnt instance, is provided at each end.

with guide lugs 10,-which lugsare-intended to sl de 'on the cylindrical surface being 01;).-

erated on to limit the depthpof cut of" theblade which is carried by the clamping head between the two guideslugs l0.

The blade 3 is preferably shorter than thev space between the guide lugs 10 and has its scraplng surface curved 1n convexform with;

the radius of the curvature preferably'less than the ItCllUS of a cylinder on which the tool is to operate, as s hown. The blade may" be freely removed from between the clamp-' mg members upon aloosenlng of the same,

or may be set in any position of adjustment relative thereto as desired. The upper or inner edge of the blade 3 is recessed to adapt 't to fit around the stem 5. 1

In the use of my tool the-blade is properly adjusted to suit the bore of the cylinder on which it is to operate by placing the tool in a true cylinder of the size desired with the lugs 10 in contact with the wall thereof and with the blade 3 free to adjust itself to the cylinder so that a perfect three point contact is had between the tool and cylinder wall. The clamping head is then tightened to firmly hold the blade in the adjusted'position by a 25 clamping-head having spaced guide projecturningof the handle 6 relativeto the stem 4:. The tool may now be used for scraping a cylinder of the size for which adjusted, the

scraping being accomplished by a reciprocating movement of the tool longitudinally of the handle. During the scraping operation the gauge points 10 will straddle the filling or other rough part to be scrapedwhich is operated on by the knife blade, the knife continuing to act thereon until the cylinder sur-' face is brought into true cylindrical "form,

V itthen being impossible to further scrape the cylinder surface due'to the depth limiting contact of the gauge pointslO therewith.

I wish it understood that my invention is not limited to any specific construction, arrangement orform of the parts as it is capable ofnumerous modifications and changes i without departing from the spirit of the claims. it I V Having thus'described my invention, what I claim as new and desire tosecure by Let a ters Patent, is, a

1. A tool for scraping protuberant por-J tions from a circular surface, comprising a tions for contact withthe surfaceacted on,

7 thetspacing ofthe projections being transverseto thesurface axis, and a thin bladelike scraping member rigidly clamped by the head between the projections.

2'. A tool for scraping protuberant portions from a cylindrical surface, comprising a clamping head having guide projections,

spaced transversely to the axis of the surface acted on, and a thin blade-like scraping member rigidly clamped by the head be tween the projections and cooperating there 7 i with to form a three-point contact with the surface a'cted on, the scraping member having its scraping edge describing a curve whlch lsof lessradius than the curvature of the surfaceacted o'n.=

A; an or theclass described, havin a handleya clamping head at an end of the handle, and a substantially flat blade-like scraping member'rigidly clamped by the head with its scraping edge transverse "to the-handle axis,,the clamping head having guide lugs at opposite ends of the scraping member and cooperating therewith to form a three-point contact with the surface acted on,- the contact points describing a curve correspondlng to the deslred curvature of such surface.

I 4:. A tool of the class described comprising a clamping head, a handle projecting from the head, a scraping blade carried by the head with its-scraping edge transverse to the handle,'said head having guide lugs at opposite ends of the blade, which cooper ate therewith to form a circular three-point contact of predetermined diameter.

- 5. A tool of the class described, comprising a clamping head having guide lugs projecting therefrom for coaction with the sur from the head, the head having guide pro-' jections at opposite ends of the blade to cooperate with-theblade to form a three point contact for engagement with the surface to be scraped; I I

ing two clamping members' forming a clamping head, one member having a hollow stem 7. A tool of the class described, 'compris-- fprojecting therefrom, a handle shouldered against an end of the stem and having a part projecting through the stem and its member and threaded into the othermember and. adjustable to impart blade clamping and releasing movements to,the;membe rs, and a blade clamped between the members and havingalongitudinally convexed scraping edge projecting from the members, one of the members having guide lugs projecting therefrom and cooperating withthe blade to form a multiplefpoint contact with a curved surface to" be scraped' In testimony. whereof I have hereunto signed my name to this specification;

q XA D. JOHNSON; 

